Link for sprinkler-heads.



LINK FUR SPRINKLER HEADS.

APPLICATION HLED DEC. 29. 1917.

Ill/VE/V TOR A TTOR/VEVS FRANCIS JOSEPH FEE, or new YORK, n. Y.

LIN K FOR SPRINKLER-HEADS.

Specification of Letters Patent.

Patented (Bot. 29, 19118.

Application filed December 29, 1917. Serial No. 209,443;

To all whom it may concern Be it known that I, FRANCIS J. FEE, a citizen of the United States, and a resident of the city of New York, borough of the Bronx, in the county of Bronx and State of New York, have invented a new and Improved Link for Sprinkler-Heads, of which the following is a full, clear, and exact description.

This invention relates to automatic devices for use in buildings, such sprinkler devices being so designed as to operate automatically to sprinkle water for the purpose of extinguishing a flame or fire that may have already caused sufficient rise in temperature in the building to melt a soft solder that normally holds the sprinkler in inactive condition. I

Among the objects of this particular inventionis to improve the character or struc ture of the fusible links that are employed in the sprinkler devices, the new structure of the links being such that they are of maximum strength consistent with reliability of operation when subjected to an abnormal temperature.

More specifically stated the invention comprises a pair of metal plates so formed as to provide a closed cavity for the accommodation of a cylindrical key, the axis of the key lying in the plane between the two plates and perpendicular to the line of stress to which the two plates are subjected in practice, said key serving while the plates are united by the soft solder as a means to sustain a large percentage of said longitudinal stress applied to the plates.

Another object of the invention is to improve the construction of the link plates in such a manner as to stiffen the same and serve to negative any tendency of either link to be turned or twisted with respect to the other plate in the plane of the plate and around an axis perpendicular to the plane in which the two plates meet.

With the foregoing and other objects in view the invention consists in the arrangement and combination of parts hereinafter described and claimed, and while the invention is not restricted to the exact details of construction disclosed or suggested herein, still for the purpose of illustrating a practical embodiment thereof reference is had to theaccompanying drawings, in which like reference characters designate the same' parts in the several views, and in which- Figure 1 is a front elevation of one of my improved links,

the meeting edges of the two plates which constitute the principal part of the link and showing a fragment of one plate broken away to disclose the cylindrical key.

only in dotted lines.

ig. 3 is a vertical sectional view indicatmg to which the link is secured in practice.

Fig. 4 is a perspective view of the key detached; and

Fig. 5 is a horizontal sectional detail on the broken line 5-5 of Fig.1.

Referring now drawings, prising front and rear plates 11 and 12. Each of these plates is provided atone end with ahole 13 into which of the sprinkler head arm is adapted to project in a manner well understood in the art and. not requiring illustration. Suflice it to say, however, that the two sprinkler head arms act upon the loop portions 14 of the two plates tending to separate the plates longitudinally of each other.

registers with the hole to point out, however, particularly that the notched portion of each plate is practically coextensive with the notch and bail portions of the opposite link and with which the notch registers. The side edges or walls of the notches may be flared somewhat from each other and yet not enough to materially reduce or affect the length of said edges which have an important function in stiffening the link and preventing, in combination with other features to be described, any tendency for the links to rotate with relation to each other around a transverse central axis.

The two plates are provided with outwardly formed semi-cylindrical hollow projections 16 which are arranged preferably at the centers of the plates and hence register with each other when the plates are assembled. thus forming a cylindrical cavity in which is housed and completely inclosed a cylindrical key 17 preferably of relatively hard metal, the central axis of the key lying indicating especially the manner of applying the solder all around the action of the two links with respect to the key at the moment of separation of j the plates and collapse of the sprinkler head more particularly to the I show a complete link 10 comthe hook or prong At the opposite end from the hole 13 and bail If each link is provided with a notch 15 which in general cially throughout their meeting surfaces and also the inner surface of the cavity is likewise tinned. The tinning, however, is relatively thin and so while the key 17 is ut in place and the plates are heated the adjacent surfaces of the plates are brought into relatively intimate contact with each other or are practically soldered in actual contact so as to meet each other in the same plane. As will be appreciated from Fig. 2 with a force pulling upward on the plate 11 and another force pulling downward on the plate 12 a large percentage of this force is resisted by the key, said force tending toshear the key in a longitudinal and diametrical plane coinciding with the plane of union between the plates, or as indicated in Fig. 3 the two plates have oppositely arranged shoulders 18 which bear against diametrically opposite portions of the key and so sustain the force just referred to. There is a moment, however, tending to cause rotation of the upper shoulder 18 around the key and other shoulder as indicated in Fig.

3, and this turning or rolling moment insures what constitutes virtually a bodily movement or separation of one plate with respect to the other, a most important function in this art where the tendency of cold flow of the soft solder must be resisted for a long period of time even though .the force tending to separate the plate and cause the collapse of the sprinkler head may be considerable.

While the structure forming the cavity and the position and action of the key are such as to tend to prevent relative rotation of the plates around the transverse axis, I have found in my extensive experience in this art that it is of vital importance to offset any possibility of such rotation even to a very slight extent. Therefore. I providea series of lugs 19 on one plate cooperating in depressions 20 of the other plate. These cooperating lugs and depressions are arranged at what might be termed the remote corners of the plates or as far as expedient from the central cavity, and hence when these features are made to coincide in pairs in the assemblage of the plates there can be no possibility of either plate sliding in any direction or rotating over the surface of the other plate while the fusible .formation of the notches 15. The legs of solder 21 which bound said long edges of each notch and unite the same to the bail portion 14 of the next adjacent plate add very materially" to the'stifi'ness and strength of the link tending to resist both the normal longitudinal strain and the possibility of rotation of one plate over the other.

I claim:

1. The herein described link for automatic sprinkler heads, the-same comprising a pair of plates each formed at its center with a semi-cylindrical pocket having an unbroken outer wall, the two pockets of the two plates being adapted to register forming a cylindrical cavity, the two adjacent faces of the plates meeting in a plane, a cylindrical key located in said cavity and completely housed by the walls thereof, the

axis of the key lying in said plane of contact between the plates and perpendicular to the normal strain applied to the plates tending to separate them, and means serving to hold the plates normally together in direct contact with each other and preventing the movement of either in any direction with respect to the other plate.

2. In a link for sprinkler heads, the combination of a pair of plates .each formed with a central pocket of semi-cylindrical form. the two pockets when registering forming a cylindrical cavity the axis of which is perpendicular to the line of strain applied to the links tending to separate them in practice, a hard metal cylindrical key fitted in said cavity and completely inclosed by the walls thereof. each plate having adjacent to one end a hole bounded by a bail while the adjacent end of the other plate is provided with a longitudinal notch coinciding substantially with the length of the hole and bail aforesaid, said plates being furthermore provided with cooperating pairs of lugs and depressions remote from the central cavity, and a line of solder ap plied entirely around the line representing the surface contact between the two plates, said solder extending therefore lengthwise along the side edges of the plate notches.

FRANCIS JOSEPH FEE. 

